Layered Wood Composites

ABSTRACT

A method for the preparation of a composite product, as well as the composite product. The composite product comprises at least two layers. At least one of the layers is of wood or another cellulose-containing material. The process comprises differentially treating the layers prior to, during, or after the lamination of the layers into a composite product.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. Provisional application No.60/711,202, filed on Aug. 25, 2005, the disclosure of which is herebyincorporated by reference.

BACKGROUND OF THE INVENTION

Composite cellulosic products are often treated in order to impartdesirable qualities such as insect resistance, durability and hardness.Such methods generally involve treating a composite product after it hasbeen formed from component layers, or treating a surface layer prior toits lamination to core lamellae. Such core lamellae, if multilayered,are generally of layers which have been identically treated prior totheir assembly into a composite product with the surface veneer.

A review entitled “Wood Composite Protection” [Gardner, Douglas J.;Tascioglu, Cihat; Walinder, Magnus E. P.; ACS Symposium Series (2003),845 (Wood Deterioration and Preservation), 399-419] discloses thepre-assembly treatment of wood layers with a solution of CCA (page 404,second paragraph).

A Japanese Patent, JP 2001279917 to Hisao Iwamoto, discloses thetreatment of a single veneer with an insecticide, followed by theattachment of the veneer to a surface veneer. The reference alsodiscloses that a cosmetic coating can be applied to the surface veneerafter assembly (paragraph 0013).

A German journal article entitled “Protective Treatment of BuildingPlywood” [Deppe, H. J.; Bundesanst. Mater., Berlin-Dahlem, Fed. Rep.Ger.; Holz als Roh-und Werkstoff (1986), 44(9), 333-40] disclosestreatment of two layers—a surface layer and an underlayer (“corelamella”)—with a preservative by different processes prior to theirassembly into a composite wood product. That the underlayer can be ofmultiple veneers (core lamellae) is also disclosed. A process whichincludes the treatment of the core lamella with and a simple immersionfor the surface sheets is disclosed (see Conclusion). However, noapplications involving the differential treatment of multiple woodlayers such as veneers and laminates prior to assembly into a multilayercomposite product are disclosed.

There exists a need for a process which can be used to prepare a woodproduct having an internal distribution of a process parameter such as,for example, a biocide, which can be precisely tailored such that thecharacteristics of the wood are appropriate for the wood's intended use.There is also a need for such a wood product.

SUMMARY OF THE INVENTION

Provided is a method for the preparation of a composite product, as wellas the composite product. The composite product comprises at least twolayers. At least one of the layers is of wood or anothercellulose-containing material. The process comprises differentiallytreating the layers prior to, during, or after the lamination of thelayers into a composite product.

DETAILED DESCRIPTION OF THE INVENTION

“Veneer” as used herein, denotes wood which is of a thickness to be usedin a layered wood product. Typical veneers generally have a thickness oftwo inches or less, although thicker veneers can be used if required byan application. “Composite product” denotes a product made of multipleveneers, i.e., in numbers as low as two and as high as, for example,100. The number of veneers in a composite product can be even or odd.The thicknesses of the multiple veneers in a composite product cancorrespond to any of a wide range of thickness distributions. Theveneers in the composite product can be oriented such that the grains ofoverlying veneers are oriented at any angle to overlying and underlyingveneers. For example, the grains of two veneers in a composite productcan be parallel or mutually perpendicular, or at other angles withrespect to each other.

Veneers can be lumber, “composite wood products” including but notrestricted to wood laminates, plywood, LVL, OSB, PSL, Particleboard,GLUELAM, MDF, wood plastic composite, plastic composite, cementcomposite, plastic, or other “composite wood products” comprisingplastic, polymers, wood, cement, metal or other cellulose materials,wood, partial wood or alternative materials.

Lumber is often made from recycled wood and plastic. Wood PlasticComposites typically consist of a mix of wood fibers from recovered sawdust and waste plastics that include high-density polyethylene, PVC(polyvinyl chloride), as well as other types of thermoset plasticpolymers. A common mixture is 50/50 by weight. The material is formedinto both solid and hollow profiles. The wood fibers generally act asreinforcement, and thus Recycled wood/plastic composites are typicallymore rigid than 100 percent recycled plastic lumber. In addition, theplastic may encapsulate and bind the wood together to resist moisturepenetration and degradation from fungal rot.

Another example of material from which veneers can be made is HighDensity Polyethylene (HDPE). HDPE is a common resin used by thethermoplastics industry to make products from toys to packaging. Thisresin is particularly suitable because of its high extrusion viscosity,dimensional stability, and compatibility with other ingredients.

Polyvinyl Chloride (PVC) is a common thermoplastic used in themanufacture of building products and is also a suitable material fromwhich veneers can be made. The material is particularly suitable becauseof its high stiffness capability, high mechanical strength, modest cost,and excellent weather resistance.

Cellulose fiber-reinforced cement can also be used in the manufacturingof veneers. For example, fiber-cement building boards are made bycombining, silica (quartz), calcium silicate, and cellulose fiber, forexample, in a 40:50:10 weight ratio, and water. A rigid fiber-cementproduct material which is formed under heat and pressure is to a largeextent moisture proof, fire proof, resistant to decay and termites. Thematerial can be made to be highly UV resistant if inorganic pigments areadded to the material mixture.

The term “composite products” as used herein means layered wood productsmade from veneers as defined above.

Different veneers can be in different layers, or they can be part of thesame layer. For instance, veneers can be laterally placed with respectto one another (i.e., multiple veneers side-by-side to for a singlelayer). In this way, parameters such as compound, concentration, numberof compounds, etc., can vary laterally across the face of the compositeproduct, as well as with depth.

The term “layer” as used herein means an individual veneer which is acomponent of the “composite product.” i.e., laminates, except when twoor more veneers are laterally placed with respect to each other, inwhich case, a “layer” can comprise multiple veneers.

The uppermost or outermost layer of the composite product, sometimesused as a decorative layer in this application is also referred to as“finishing layer,” which is laminated to a substrate in the compositeproduct or included during the manufacturer of the composite product.

When used in reference to a composite which has layers of more than onematerial, “differential treatment” means the layers of the composite aretreated with different modalities or with the same modalities.Modalities can include treatment with a compound or composition,exposure to heat, light or electromagnetic radiation, or other means oftreatment. When used in reference to a composite which has multiplelayers of the same material, the term “differential treatment” means thelayers are treated with different modalities.

In one embodiment, differential treatment can mean the treatment ofdifferent component layers with different compounds prior to theirassembly into a composite wood product. A non-limiting example is thetreatment of two component layers, a first and second layer, with abiocide and color stain, respectively, after or prior to assembly.

In another embodiment, differential treatment can mean treatment ofdifferent layers within the same composite product prior to or afterassembly into a composite product. A non-limiting example is thecreation of a layered gradient of treatments within the compositeproduct; if desired, the treatment of the layers intended to bepositioned as outer layers can be treated to a higher concentration of abiocide than layers intended to be positioned as inner layers. In thisway, the presence of biocide at interior positions in the wood productis assured, yet the composite product can be engineered to reflect thereduced exposure of the inner layers to biological deterioration,weathering, UV or fire, the risk of the exposure of the compositeproduct to fungi, decay, rot, insect attack, termites includingmastotermes, macrotermes and coptoptermes species including formosanus.The method of the present invention allows the fabrication of acomposite product in which the concentration of a treatment compound oradditive can vary with the position of a veneer in a composite product.The variation of concentration with layer can be tailored to meet theintended use of the composite product. Examples of compounds which canbe varied include insecticides, termiticides, fungicides, algaecides,additives, fire retardants, UV blockers, water repellents, mineral oils,vegetable oils, drying oils, resins , polymers, acrylics, isocyanates,wood hardeners, dyes, pigments, colorants or combination of the above indifferent diluents as water, organic solvents, white spirits, light oil,other hydrocarbons, drying oils, linseed oil, fish oils throughout. Thevarying concentration can reflect the spatially varying parametersencountered in a given application.

In yet another embodiment differential treatment is the treatment oflayers such that some layers contain fewer or greater numbers ofcompounds than other layers. An example is the treatment of componentlayers with a biocide, where the component layer which is to be thesurface layer additionally treated with a compound which improvesdurability, such as a compound which imparts to the wood an increasedresistance ultraviolet radiation. It is thus within scope of the presentinvention to treat some or all layers with a first treatment, followedby the treatment of some, but not all, of these layer with a secondtreatment, etc., after or prior to assembly.

In general, “differential treatment” includes the treatment, after orprior to assembly, of at least two component layers, in a manner suchthat they contain different additive compounds, concentrations ofadditive compounds, or number of additive compounds.

The term “differential treatment” can include the treatment of acomposite product after it has been assembled. For example, a compositeproduct which comprises layers of both wood and a substance requiringcuring can be assembled prior to complete curing. Additional curing canbe done after assembly.

In some cases, it may be desirable to allow one or more veneers toremain untreated. For example, inner layers of wood or other materialsmay be shielded from the elements by outer layers, and there may be noneed to treat them for insect and fungus resistance, uv resistance, fireresistance, etc.

Treatment compounds which can be used in the product and method of thepresent invention are compounds such as biocides (fungicides,insecticides, bactericides, moldicides, termiticides, etc.); paints,stains, colorants, pigments, pre-coats, wear and weather resistors, UVblockers wood hardening compounds, fire retardants.

The present invention also provides methods for making the compositeproduct. One of the methods comprises the steps 1) differentiallytreating two or more component layers, and 2) fabricating a compositewood product by laminating the two or more layers into a compositeproduct. In one embodiment, the component layers are laminated such thatone of the two or more component layers is the surface layer of thecomposite product. In a further embodiment, the component layers arelaminated such that another of the two or more component layers isattached to the surface layer. A second example comprises the followingsteps: 1) treating the layers after or prior to the manufacturing of thecomposite product; 2) assembling the layers into a composite product;and 3) treating the composite product with a second treatment that willprovide a “differential treatment” on the outer layers of the compositeproduct. A third example comprises the following steps: 1) treating thecomposite product as in examples 1 or 2; and adding additional layers toform another composite product. These added layers can be inert materialsuch as wood/plastic composite, other plastics, synthetic polymers,resin type layers or film that provide the composite product withdifferent characteristics. Other examples may comprise a combination ofthe previous examples.

The final configuration of layers depends upon the performance neededfor a given end-use service application. For example, a low performancecomposite product may comprise biocide treated component layers, withsurface layers being additionally treated with water-repellent polymersand UV resistant pigments. A higher performance composite product, foruse in, for example, decking, may comprise core layers which are treatedwith biocide, water repellent polymers and UV resistant pigments, andsurface layers which are similarly treated, but also include a woodhardener to protect against abrasion and wear. The present inventionprovides the ability to meet specific performance requirements forselected service needs or market economic targets.

Examples of composite products which can be made according to the methodinclude, but are not limited to, plywood, laminated veneer lumber (LVL),I-joist, other veneer based products, glued laminated lumber orGLUE-LAM, block board, oriented stranded board (OSB), parallel strandedboards (PSB), particleboard, medium density boards (MDF), woodlaminates, and other products which are layer-based; wherein the layersare comprised of wood, partial wood or alternative materials; wherein atleast one of the layers is or comprises a cellulosic material. Thecomposite product can be engineered for use in a wide range ofconditions and applications such as, for example, indoor, outdoorconditions and/or in-ground contact.

In one embodiment, the outer, exposed surface component layers arechemically treated with biocides, pigments and weather durable polymercompounds to shield and protect the inner component layers, which mayonly be treated with biocides and pigments. In a further embodiment,decking or fencing board could be produced with the necessary biocideprotection throughout the entire board product, with added weatherdurability needed on the outer exposed faces for best total protectionagainst wood destroying organisms and weather degradation.

Additives such as, for example, pigments, dyes, fire retardants,biocides, etc. Examples of pigments which can be used are uvstabilizers. Non-limiting examples of UV stabilizers include UV lightabsorbers such as complex substituted aromatic compounds, UV lightstabilizers such as complex hindered tertiary amines, and anti-oxidants.

If desired, pigments can be included in the composition. The pigmentswhich can be used in the compositions of the present invention includeinorganic and organic pigments. Inorganic pigments include compounds ofmetals such as iron, zinc, titanium, lead, chromium, copper, cadmium,calcium, zirconium, cobalt, magnesium, aluminum, nickel, and othertransition metals. Carbon black is also an inorganic pigment.

Some non-limiting examples of suitable inorganic pigments include: ironoxides, including red iron oxides, yellow iron oxides, black iron oxidesand brown iron oxides; carbon black, iron hydroxide, graphite, blackmicaceous iron oxide; aluminum flake pigments, pearlescent pigments;calcium carbonate; calcium phosphate; calcium oxide; calcium hydroxide;bismuth oxide; bismuth hydroxide; bismuth carbonate; copper carbonate;copper hydroxide; basic copper carbonate; silicon oxide; zinc carbonate;barium carbonate; barium hydroxide; strontium carbonate; zinc oxide;zinc phosphate; zinc chromate; barium chromate; chrome oxide; titaniumdioxide; zinc sulfide and antimony oxide, lead chrome, and cadmiumpigments.

Preferred inorganic pigments are carbon black; graphite; iron oxides,including yellow, red, black and brown iron oxides; zinc oxide; titaniumoxide and aluminum-based pigments, such as, for example Al₂O₃ Al(OH)₃.

Non-limiting examples of organic pigments include Monoazo (arylide)pigments such as PY3, PY65, PY73, PY74, PY97 and PY98; Disazo(diarylide); Disazo condensation; Benzimidazolone; Beta Naphthol;Naphthol; metal-organic complexes; Isoindoline and Isoindolinone;Quinacridone; perylene; perinone; anthraquinone; diketo-pyrrolo pyrrole;dioxazine; triacrylcarbonium; the phthalocyanine pigments, such ascobalt phthalocyanine, copper phthalocyanine, copper semichloro- ormonochlorophthalocyanine, copper phthalocyanine, metal-freephthalocyanine, copper polychlorophthalocyanine, etc.; organic azocompounds; organic nitro compounds; polycyclic compounds, such asphthalocyanine pigments, quinacridone pigments, perylene and perinonepigments; diketopyrrolo-pyrrole(DPP) pigments; thioindigo pigments;dioxazine pigments; quinophthalone pigments; triacrylcarbonium pigments,and Diaryl pyrrolopyroles, such as PR254.

Non-limiting examples of fire retardants include phosphorus compoundssuch as ammonia phosphate, ammonia polyphosphate, guanidine phosphateand melamine phosphate, boron compounds such as zinc borate and boricacid, metal carbonates such as Huntite (3MgCO₃xCaCO₃) and Hydromagnesite(Mg₅(CO₃)₄(OH)₂x4H₂O), metal hydroxides such as aluminum trihydroxideand magnesium hydroxide, organic halogen compounds such as chlorinatedparaffins and brominated compounds, and urea can also be included inthis composition. The halogenated materials may be used alone ortogether with antimony compounds such as antimony trioxide or antimonypentoxide which are thought to act as synergists.

Examples of biocides include water soluble or water insoluble inorganicor organic fungicides, insecticides, moldicides, bactericides,algaecides, such as for example, azoles, quaternary ammonium compounds,borate compounds, fluoride compounds and combinations thereof.

Some non-limiting examples of water insoluble organic biocides arelisted as follows.

Aliphatic Nitrogen Fungicides

-   butylamine; cymoxanil; dodicin; dodine; guazatine; iminoctadine    Amide Fungicides-   carpropamid; chloraniformethan; cyazofamid; cyflufenamid;    diclocymet; ethaboxam; fenoxanil; flumetover; furametpyr;    prochloraz; quinazamid; silthiofam; triforine benalaxyl;    benalaxyl-M; fuiralaxyl; metalaxyl; metalaxyl-M; pefurazoate;    benzohydroxamic acid; tioxymid; trichlamide; zarilamid; zoxamide;    cyclafuramid; furmecyclox dichlofluanid; tolylfluanid    benthiavalicarb; iprovalicarb; benalaxyl; benalaxyl-M; boscalid;    carboxin; fenhexamid; metalaxyl; metalaxyl-M; metsulfovax; ofurace;    oxadixyl; oxycarboxin; pyracarbolid; thifluzamide; tiadinil;    benodanil; flutolanil; mebenil; mepronil; salicylanilide;    tecloftalam; fenfuram; furalaxyl; furcarbanil; methfuroxam;    flusulfamide    Antibiotic Fungicides-   aureofungin; blasticidin-S; cycloheximide; griseofulvin;    kasugamycin; natamycin; polyoxins; polyoxorim; streptomycin;    validamycin; azoxystrobin; dimoxystrobin; fluoxastrobin;    kresoxim-methyl; metominostrobin; orysastrobin; picoxystrobin;    pyraclostrobin; trifloxystrobin    Aromatic Fungicides-   biphenyl; chlorodinitronaphthalene; chloroneb; chlorothalonil;    cresol; dicloran; hexachlorobenzene; pentachlorophenol; quintozene;    sodium pentachlorophenoxide; tecnazene    Benzimidazole Fungicides-   benomyl; carbendazim; chlorfenazole; cypendazole; debacarb;    fuberidazole; mecarbinzid; rabenzazole; thiabendazole    Benzimidazole Precursor Fungicides-   furophanate; thiophanate; thiophanate-methyl    Benzothiazole Fungicides-   bentaluron; chlobenthiazone; TCMTB    Bridged Diphenyl Fungicides-   bithionol; dichlorophen; diphenylamine    Carbamate Fungicides-   benthiavalicarb; furophanate; iprovalicarb; propamocarb;    thiophanate; thiophanate-methyl; benomyl; carbendazim; cypendazole;    debacarb; mecarbinzid; diethofencarb    Conazole Fungicides-   climbazole; clotrimazole; imazalil; oxpoconazole; prochloraz;    triflumizole; azaconazole; bromuconazole; cyproconazole;    diclobutrazole; difenoconazole; diniconazole; diniconazole-M;    epoxiconazole; etaconazole; fenbuconazole; fluquinconazole;    flusilazole; flutriafol; furconazole; furconazole-cis; hexaconazole;    imibenconazole; ipconazole; metconazole; myclobutanil; penconazole;    propiconazole; prothioconazole; quinconazole; simeconazole;    tebuconazole; tetraconazole; triadimefon; triadimenol;    triticonazole; uniconazole; uniconazole-P    Dicarboximide Fungicides-   famoxadone; fluoroimide; chlozolinate; dichlozoline; iprodione;    isovaledione; myclozolin; procymidone; vinclozolin; captafol;    captan; ditalimfos; folpet; thiochlorfenphim    Dinitrophenol Fungicides-   binapacryl; dinobuton; dinocap; dinocap-4; dinocap-6; dinocton;    dinopenton; dinosulfon; dinoterbon; DNOC    Dithiocarbamate Fungicides-   azithiram; carbamorph; cufraneb; cuprobam; disulfiram; ferbam;    metam; nabam; tecoram; thiram; ziram; dazomet; etem; milneb;    mancopper; mancozeb; maneb; metiram; polycarbamate; propineb; zineb    Imidazole Fungicides-   cyazofamid; fenamidone; fenapanil; glyodin; iprodione; isovaledione;    pefurazoate; triazoxide    Morpholine Fungicides-   aldimorph; benzamorf; carbamorph; dimethomorph; dodemorph;    fenpropimorph; flumorph; tridemorph    Organophosphorus Fungicides-   ampropylfos; ditalimfos; edifenphos; fosetyl; hexylthiofos;    iprobenfos; phosdiphen; pyrazophos; tolclofos-methyl; triamiphos    Oxathim Fungicides-   carboxin; oxycarboxin    Oxazole Fungicides-   chlozolinate; dichlozoline; drazoxolon; famoxadone; hymexazol;    metazoxolon; myclozolin; oxadixyl; vinclozolin    Pyridine Fungicides-   boscalid; buthiobate; dipyrithione; fluazinarn; pyridinitril;    pyrifenox; pyroxychlor; pyroxyfur    Pyrimidine Fungicides-   bupirimate; cyprodinil; diflumetorim; dimethirimol; ethirimol;    fenarimol; ferimzone; mepanipyrim; nuarimol; pyrimethanil; triarimol    Pyrrole Fungicides-   fenpiclonil; fludioxonil; fluoroimide    Quinoline Fungicides-   ethoxyquin; halacrinate; 8-hydroxyquinoline sulfate; quinacetol;    quinoxyfen    Quinone Fungicides-   benquinox; chloranil; dichlone; dithianon    Quinoxaline Fungicides-   chinomethionat; chlorquinox; thioquinox    Thiazole Fungicides-   ethaboxam; etridiazole; metsulfovax; octhilinone; thiabendazole;    thiadifluor; thifluzamide    Thiocarbamate Fungicides-   methasulfocarb; prothiocarb    Thiophene Fungicides-   ethaboxam; silthiofam    Triazine Fungicides-   anilazine    Triazole Fungicides-   bitertanol; fluotrimazole; triazbutil    Urea Fungicides-   bentaluron; pencycuron; quinazamid    Other Fungicides-   acibenzolar; acypetacs; allyl alcohol; benzalkonium chloride;    benzamacril; bethoxazin; carvone; chloropicrin; DBCP; dehydroacetic    acid; diclomezine; diethyl pyrocarbonate; fenaminosulf; fenitropan;    fenpropidin; formaldehyde; furfural; hexachlorobutadiene;    iodomethane; isoprothiolane; methyl bromide; methyl isothiocyanate;    metrafenone; nitrostyrene; nitrothal-isopropyl; OCH; 2 phenylphenol;    phthalide; piperalin; probenazole; proquinazid; pyroquilon; sodium    orthophenylphenoxide; spiroxamine; sultropen; thicyofen;    tricyclazole

Preferred insecticides which can be mixed with non-aqueous waterrepellent composition disclosed in the present invention are:

Antibiotic Insecticides

-   allosamidin; thuringiensin; spinosad; abamectin; doramectin;    emamectin; eprinomectin; ivermectin; selamectin; milbemectin;    milbemycin oxime; moxidectin    Botanical Insecticides-   anabasine; azadirachtin; d-limonene; nicotine; pyrethrins cinerins;    cinerin I; cinerin II; jasmolin I; jasmolin II; pyrethrin I;    pyrethrin II; quassia; rotenone; ryania sabadilla    Carbamate Insecticides-   bendiocarb; carbaryl; benfuracarb; carbofuran; carbosulfan;    decarbofuran; furathiocarb; dimetan; dimetilan; hyquincarb;    pirimicarb; alanycarb; aldicarb; aldoxycarb; butocarboxim;    butoxycarboxim; methomyl; nitrilacarb; oxamyl; tazimcarb;    thiocarboxime; thiodicarb; thiofanox; allyxycarb; aminocarb;    bufencarb; butacarb; carbanolate; cloethocarb; dicresyl; dioxacarb;    EMPC; ethiofencarb; fenethacarb; fenobucarb; isoprocarb; methiocarb;    metolcarb; mexacarbate; promacyl; promecarb; propoxur; trimethacarb;    XMC; xylylcarb    Dinitrophenol Insecticides-   dinex; dinoprop; dinosam; DNOC; cryolite; sodium hexafluorosilicate;    sulfluramid    Formamidine Insecticides-   amitraz; chlordimeform; formetanate; formparanate    Fumigant Insecticides-   acrylonitrile; carbon disulfide; carbon tetrachloride; chloroform;    chloropicrin; para-dichlorobenzene; 1,2-dichloropropane; ethyl    formate; ethylene dibromide; ethylene dichloride; ethylene oxide;    hydrogen cyanide; iodomethane; methyl bromide; methylchloroform;    methylene chloride; naphthalene; phosphine; sulfuryl fluoride;    tetrachloroethane    Insect Growth Regulators-   bistrifluron; buprofezin; chlorfluazuron; cyromazine; diflubenzuron;    flucycloxuron; flufenoxuron; hexaflumuron; lufenuron; novaluron;    noviflumuron; penfluron; teflubenzuron; triflumuron; epofenonane;    fenoxycarb; hydroprene; kinoprene; methoprene; pyriproxyfen;    triprene; juvenile hormone I; juvenile hormone II; juvenile hormone    III; chromafenozide; halofenozide; methoxyfenozide; tebufenozide;    α-ecdysone; ecdysterone; diofenolan; precocene I; precocene II;    precocene III; dicyclanil    Nereistoxin Analogue Insecticides-   bensultap; cartap; thiocyclam; thiosultap; flonicamid; clothianidin;    dinotefuran; imidacloprid; thiamethoxam; nitenpyram nithiazine;    acetamiprid; imidacloprid; nitenpyram; thiacloprid    Organochlorine Insecticides-   bromo-DDT; camphechlor; DDT; pp′-DDT; ethyl-DDD; HCH; gamma-HCH;    lindane; methoxychlor; pentachlorophenol; TDE; aldrin; bromocyclen;    chlorbicyclen; chlordane; chlordecone; dieldrin; dilor; endosulfan;    endrin; HEOD; heptachlor; HHDN; isobenzan; isodrin; kelevan; mirex    Organophosphorus Insecticides-   bromfenvinfos; chlorfenvinphos; crotoxyphos; dichlorvos;    dicrotophos; dimethylvinphos; fospirate; heptenophos;    methocrotophos; mevinphos; monocrotophos; naled; naftalofos;    phosphamidon; propaphos; schradan; TEPP; tetrachlorvinphos;    dioxabenzofos fosmethilan phenthoate; acethion; amiton; cadusafos;    chlorethoxyfos; chlormephos; demephion; demephion-O; demephion-S;    demeton; demeton-O; demeton-S; demeton-methyl; demeton-O-methyl;    demeton-S-methyl; demeton-S-methylsulphon; disulfoton ethion;    ethoprophos; IPSP; isothioate; malathion; methacrifos;    oxydemeton-methyl; oxydeprofos; oxydisulfoton phorate; sulfotep;    terbufos; thiometon amidithion; cyanthoate; dimethoate;    ethoate-methyl; formothion mecarbam; omethoate; prothoate;    sophamide; vamidothion chlorphoxim; phoxim; phoxim-methyl    azamethiphos; coumaphos; coumithoate; dioxathion; endothion;    menazon; morphothion; phosalone; pyraclofos; pyridaphenthion;    quinothion; dithicrofos; thicrofos; azinphos-ethyl; azinphos-methyl;    dialifos; phosmet; isoxathion; zolaprofos; chlorprazophos;    pyrazophos; chlorpyrifos; chlorpyrifos-methyl; butathiofos;    diazinon; etrimfos; lirimfos; pirimiphos-ethyl; pirimiphos-methyl;    primidophos; pyrimitate; tebupirimfos; quinalphos;    quinalphos-methyl; athidathion; lythidathion; methidathion;    prothidathion; isazofos; triazophos; azothoate; bromophos;    bromophos-ethyl; carbophenothion; chlorthiophos; cyanophos;    cythioate; dicapthon; dichlofenthion; etaphos; famphur;    fenchlorphos; fenitrothion; fensulfothion; fenthion; fenthion-ethyl;    heterophos; jodfenphos; mesulfenfos; parathion; parathion-methyl;    phenkapton; phosnichlor; profenofos; prothiofos; sulprofos;    temephos; trichlormetaphos-3; trifenofos; butonate; trichlorfon;    mecarphon; fonofos; trichloronat; cyanofenphos; EPN; leptophos;    crufomate; fenamiphos; fosthietan; mephosfolan; phosfolan;    pirimetaphos; acephate; isocarbophos; isofenphos; methamidophos;    propetamphos; dimefox; mazidox; mipafox    Oxadiazine Insecticides-   indoxacarb    Phthalimide Insecticides-   dialifos; phosmet; tetramethrin    Pyrazole Insecticides-   acetoprole; ethiprole; fipronil; tebufenpyrad; tolfenpyrad;    vaniliprole    Pyrethroid Insecticides-   acrinathrin; allethrin; bioallethrin; barthrin; bifenthrin;    bioethanomethrin; cyclethrin; cycloprothrin; cyfluthrin;    beta-cyfluthrin; cyhalothrin; gamma-cyhalothrin; lambda-cyhalothrin;    cypermethrin; alpha-cypermethrin; beta-cypermethrin;    theta-cypermethrin; zeta-cypermethrin; cyphenothrin; deltamethrin;    dimefluthrin; dimethrin; empenthrin; fenfluthrin; fenpirithrin;    fenpropathrin; fenvalerate; esfenvalerate; flucythrinate;    fluvalinate; tau-fluvalinate; furethrin; imiprothrin; metofluthrin;    permethrin; biopermethrin; transpermethrin; phenothrin; prallethrin;    profluthrin; pyresmethrin; resmethrin; bioresmethrin; cismethrin;    tefluthrin; terallethrin; tetramethrin; tralomethrin; transfluthrin;    etofenprox; flufenprox; halfenprox; protrifenbute; silafluofen    Pyrimidinamine Insecticides-   flufenerim; pyrimidifen    Pyrrole Insecticides-   chlorfenapyr    Tetronic Acid Insecticides-   spiromesifen    Thiourea Insecticides-   diafenthiuron    Urea Insecticides-   flucofuron; sulcofuron    Other Insecticides-   closantel; crotamiton; EXD; fenazaflor; fenoxacrim; hydramethylnon;    isoprothiolane; malonoben; metoxadiazone; nifluridide; pyridaben;    pyridalyl; rafoxanide; triarathene; triazamate

Preferred bactericides include:

-   bronopol; cresol; dichlorophen; dipyrithione; dodicin; fenaminosulf;    formaldehyde; hydrargaphen; 8-hydroxyquinoline sulfate; kasugamycin;    nitrapyrin; octhilinone; oxolinic acid; oxytetracycline probenazole;    streptomycin tecloftalam thiomersal

Non-biocidal products such as colorants, UV inhibitors, plasticizers,compatibility enhancing agents and the like may also be added to thesystem disclosed herein to further enhance the performance of the systemor the appearance and performance of the resulting treated products.

Examples of composite products which can be manufactured according tothe process of the present invention, including but do not restrictedboards for decking, flooring, fencing, siding, verandah posts, fencingrails, poles, posts, sleepers, landscaping products, retaining wallmaterial, sleepers, joists, bearers, beams, columns and trusses as wellas other applications in which it is desirable that core layers bedifferentially treated for functional and economic reasons.

Methods of lamination which can be used in the process of the presentinvention use resins and glues including but not restricted to phenolformaldehyde, urea formaldehyde, melanine urea formaldehyde, otherformaldehyde based resins, Polyvinyl Acetate, polyurethane, isocyanates,polyesters, acrylic, epoxy resins or natural resins as casein or resinfrom animals such as mussels, or a combination of the above. Theseresins can be applied by itself or in a “glue” comprising additionalfunctional ingredients. Glues include fillers, examples of which includewheat, macadamia and rice flour. A second ingredient of the glue can bethe catalyst, this can be very diverse and will depend on the type ofresin used, the most common one is soda ash or caustic soda for phenolformaldehyde type resins, as extender is normally use water but otherdiluents can be used.

The resin or glue is spread by spraying, brushing or rolling onto thesurfaces of the layers to be joined together. The layers are pressedtogether using a range of pressures from atmospheric up to 3,000 psi orgreater, and can be constant or varied during the pressing stage of themanufacturing procedure. The pressures Temperatures, often in the rangeof from room-temperature to 500° C., can be used to in the process,before, during or after the pressure period. Temperature used can bevariable. Other parameters or physical conditioning can be used duringthe manufacturing process and more specific during the gluing of Layers,this can be microwave, high frequency, steam, gasses of CO₂, Nitrogen,ammonia, and other gases.

EXAMPLES Example 1

A Four Laminate Decking Board Product

The top laminate (veneer) of a dry, less than 15% moisture content,solid wood having a thickness of 0.25 inches will be impregnated using avacuum pressure process with an appropriate biocide formulation withadditional performance enhancing additives. The biocide formulation willcontain 5 parts tebuconazole, (a fungicide) and 1 part bifenthrin, (aninsecticide) and will be impregnated into the wood at a active biocideretention of 0.012 pcf to protect against wood rot, decay, and termiteattack. Additionally, 45 parts per million of an effective moldicidesuch as an isothiazolone compound will be added to the tebuconazole andbifenthrin mixture prior to the impregnation step to add additionalprotection to the treated wood against mold and mildew attack. Thefungicide, insecticide, and moldicide mixture will also be combinedprior to impregnation into the wood with durable UV resistant inorganiciron oxide color pigments and a mixture of hydrophobic oils and paraffinwaxes for water repellency performance to help the top wood laminatewithstand direct exposure to the degrading effects of exterior weather,including moisture uptake which swells the wood dimension, as well asheating and harsh drying caused by direct sunlight (UV) exposure. Suchharsh drying could otherwise result in wood dimension shrinkage,particularly on horizontally positioned deck boards.

The middle two dry (less than 15% moisture content) solid wood laminates(veneers), each of 0.25 inches thickness will add needed bending andcompressive strength to the wood laminate deck board product. The middletwo solid wood laminates each will be impregnated using a vacuumpressure process with an appropriate biocide formulation. The biocideformulation will contain 5 parts tebuconazole, (a fungicide) and 1 partbifenthrin, (an insecticide) and will be impregnated into the wood at anactive biocide retention of 0.012 pcf to protect against wood rot,decay, and termite attack. Additionally, 45 parts per million of aneffective moldicide such as an isothiazolone compound will be added tothe tebuconazole and bifenthrin mixture prior to the impregnation stepto add additional protection to the treated wood against mold and mildewattack. A wood hardening, strength enhancing monomer such asdicyclopentadiene, Poly-DCPD, a plastic resin polymer, can also be addedto the biocide treatment formulation prior to the impregnation step. ThePoly-DCPD will be impregnated into the wood at retention of 15 pcf andthen polymerized in the wood using specific catalysts to control thepolymerization process to add, in this case, additional bending andcompressive strength properties to the finished wood laminate deck boardproduct.

A bottom laminate (veneer) of a dry, (less than 15% moisture content)solid wood having a thickness of 0.25 inches will be impregnated using avacuum pressure process with an appropriate biocide formulation. Thebiocide formulation will contain 5 parts tebuconazole, (a fungicide) and1 part bifenthrin, (an insecticide) and will be impregnated into thewood at an active ingredient biocide retention of 0.012 pcf to protectagainst wood rot, decay, and termite attack. Additionally, 45 parts permillion of an effective moldicide such as an isothiazolone compound willbe added to the tebuconazole and bifenthrin mixture prior to theimpregnation step to add additional protection to the treated woodagainst mold and mildew attack. The treated wood laminates will then becured or re-dried after the biocide impregnation process treatment.

After differential pretreatment impregnation, then re-drying, curing ora polymerization step is undertaken resulting in the impregnated woodveneer reaching a final moisture content of less than 15%, the top, twomiddle and bottom veneers will be laminated together to form a compositeproduct by using conventional wood lamination processing whichincorporates appropriate glue resins applied between the wide faces ofthe treated solid wood veneers, placing the veneers into the desiredwide face to wide face contact in a “stacked or sandwiched”configuration, and then applying high compressive pressure in aperpendicular direction evenly across the entire wide face surface areaof the veneers using vacuum hydraulic press machinery along withelevated temperature exposure to the veneers to aid in the rapid settingand curing of the veneer bonding resins to form a solid, one piecemulti-veneer wood laminate deck board.

Example 2

A Three Laminate Decking Board Product

The top laminate (veneer) of a dry, (less than 15% moisture content)solid wood having a thickness of 0.25 inches is impregnated using avacuum pressure process with an appropriate biocide formulation withadditional performance enhancing additives. The biocide formulation willcontain oxine copper, a wood preservative and will be impregnated intothe wood at a active biocide retention of 0.02 pcf to protect againstwood rot, decay, and termite attack. Additionally, 45 parts per millionof an effective moldicide such as an isothiazolone compound will beadded to the tebuconazole and bifenthrin mixture prior to theimpregnation step to add additional protection to the treated woodagainst mold and mildew attack. The wood preservative and moldicidemixture will also be combined prior to impregnation into the wood withdurable UV resistant inorganic iron oxide color pigments. Additionally,a water resistant, wood hardening, strength enhancing monomer such asdicyclopentadiene, Poly-DCPD, a plastic resin polymer, can also be addedto the wood treatment formulation prior to the impregnation step. ThePoly-DCPD will be impregnated into the wood at retention of 25 pcf andis then polymerized in the wood using specific catalysts to control thepolymerization process. UV resistant pigment with monomer polymerizedtop wood laminate can withstand direct exposure to the degrading effectsof exterior weather, including moisture uptake which swells the wooddimension, as well as heating and harsh drying caused by direct sunlight(UV) exposure. Such harsh drying could otherwise result in wooddimension shrinkage, particularly on horizontally positioned deckboards. The hardening monomer polymerization will also impart resistanceto surface marring, and scuffing due to abrasive foot traffic on topwood laminate horizontal decking board surface.

A middle laminate (veneer) of a dry, (less than 15% moisture content)solid wood having a thickness of 0.25 inches will be impregnated using avacuum pressure process with an appropriate biocide formulation withadditional performance enhancing additives. The biocide formulation willcontain oxine copper, a wood preservative and will be impregnated intothe wood at an active biocide retention of 0.02 pcf to protect againstwood rot, decay, and termite attack. Additionally, 45 parts per millionof an effective moldicide such as an isothiazolone compound will beadded to the tebuconazole and bifenthrin mixture prior to theimpregnation step to add additional protection to the treated woodagainst mold and mildew attack. Additionally, a water resistant, woodhardening, strength enhancing monomer such as dicyclopentadiene,Poly-DCPD can also be added to the wood treatment formulation prior tothe impregnation step. The Poly-DCPD will be impregnated into the woodat retention of 15 pcf and will then be polymerized in the wood usingspecific catalysts to control the polymerization process to add, in thiscase, additional bending and compressive strength properties to thefinished wood laminate deck board product.

A bottom laminate (veneer) of a dry (less than 15% moisture content)solid wood laminate having a thickness of 0.25 inches will beimpregnated using a vacuum pressure process with an appropriate biocideformulation with additional performance enhancing additives. The biocideformulation will contain oxine copper, a wood preservative and will beimpregnated into the wood at a active biocide retention of 0.02 pcf toprotect against wood rot, decay, and termite attack. Additionally, 45parts per million of an effective moldicide such as an isothiazolonecompound will be added to the tebuconazole and bifenthrin mixture priorto the impregnation step to add additional protection to the treatedwood against mold and mildew attack. After differential pretreatmentimpregnation, then re-drying, curing or a polymerization step will beundertaken resulting in the impregnated wood veneers reaching a finalmoisture content of less than 15%, the top, middle and bottom veneerswill be laminated together to form a composite product by usingconventional wood lamination processing which will incorporateappropriate glue resins applied between the wide faces of the treatedsolid wood veneers, placing the veneers into the desired wide face towide face contact in a “stacked or sandwiched” configuration, and thenapplying high compressive pressure in a perpendicular direction evenlyacross the entire wide face surface area of the veneers using vacuumhydraulic press machinery along with elevated temperature exposure tothe veneers to aid in the rapid setting and curing of the veneer bondingresins to form a solid, one piece multi-veneer wood laminate deck board.

Example 3

A Two Laminate Decking Board

A top laminate (veneer) having a thickness of 0.25 inches will be madefrom a wood plastic composite comprised of wood saw dust fiber and aHDPE (high density polyethylene). Wood plastic composites materialsexhibit greater dimensional stability, durability, and sunlight (UV)degradation resistant. The wood plastic composite further will becomprised of durable color, UV resistant inorganic iron oxide pigmentswhich will be added to the wood plastic composite product during thehigh temperature extrusion process to impart an aesthetic appearance tothe top weather protective laminate.

A bottom laminate of a dry (less than 15% moisture content) solid woodlaminate having a thickness of 1.0 inches will be impregnated using avacuum pressure process with an appropriate biocide formulation withadditional performance enhancing additives. The biocide formulation willcontain a copper quaternary wood preservative and will be impregnatedinto the wood at an active retention of 0.15 pcf to protect against woodrot, decay, and termite attack. Additionally, 45 parts per million of aneffective moldicide such as an isothiazolone compound will be added tothe tebuconazole and bifenthrin mixture prior to the impregnation stepto add additional protection to the treated wood against mold and mildewattack. The 1.0 inch thickness solid wood bottom laminate will supplyrigidity, and structural strength for the wood plastic composite solidwood laminate deck board product. After extrusion of the 0.25 inchthickness wood plastic composite laminate comprised of wood saw dustfiber and a HDPE (high density polyethylene), and pretreatmentimpregnation then re-drying, curing or a polymerization step will beundertaken resulting in the impregnated wood veneer reaching a finalmoisture content of less than 15%, the top wood plastic, and bottomsolid wood veneers will be laminated together to form a compositeproduct by using conventional lamination processing which incorporatesappropriate glue resins applied between the wide faces of the treatedsolid wood veneers, placing the veneers into the desired wide face towide face contact in a “stacked or sandwiched” configuration, and thenapplying high compressive pressure in a perpendicular direction evenlyacross the entire wide face surface area of the veneers using vacuumhydraulic press machinery low (ambient) temperature exposure to theveneers to aid in the rapid setting and curing of the veneer bondingresins to form a solid, one piece multi-veneer wood laminate deck board.

Example 4

A Two Laminate House Siding Board

A top laminate (veneer) having a thickness of 0.25 inches will be madefrom a cellulose fiber-reinforced cement material that is moistureproof, fire proof, resistant to decay, and termites. UV resistance,durable color will be imparted by adding inorganic iron oxide, or zincoxide pigments to the material mixture to a retention.

A bottom laminate of a dry (less than 15% moisture content) solid woodlaminate having a thickness of 0.5 inches will be impregnated using avacuum pressure process with an appropriate biocide formulation withadditional performance enhancing additives. The biocide formulation willcontain a quaternary wood preservative and will be impregnated into thewood at an active retention of 0.20 pcf to protect against wood rot,decay, and termite attack. Additionally, 45 parts per million of aneffective moldicide such as an isothiazolone compound will be added tothe tebuconazole and bifenthrin mixture prior to the impregnation stepto add additional protection to the treated wood against mold and mildewattack. The bottom solid wood laminate adds needed structural stiffnessand enhanced bending strength to the finished laminated siding product.After manufacture of the 0.25 thickness cellulose fiber-reinforcedcement material and pretreatment impregnation, then re-drying, curing ora polymerization step will be undertaken resulting in the impregnatedwood veneer reaching a final moisture content of less that 15%, the topcellulose fiber-reinforced cement and bottom solid wood veneers will belaminated together to form a composite product by using conventionallamination processing which incorporates appropriate glue resins appliedbetween the wide faces of the veneers, placing the veneers into thedesired wide face to wide face contact in a “stacked or sandwiched”configuration, and then applying high compressive pressure in aperpendicular direction evenly across the entire wide face surface areaof the veneers using vacuum hydraulic press machinery an elevatedtemperature exposure to the veneers to aid in the rapid setting andcuring of the veneer bonding resins to form a solid, one piecemulti-veneer wood laminate deck board.

1. A method of preparing a composite product comprising the steps of: a)providing at least a first veneer and a second veneer; b) differentiallytreating at least two of said veneers; and c) assembling said veneersinto a first composite product.
 2. A method of preparing a compositeproduct as in claim 1 wherein the first veneer is a finishing layer. 3.A method of preparing a composite product as in claim 2 wherein step bcomprises providing a treatment solution comprising a fungicide and aninsecticide.
 4. A method of preparing a composite product as in claim 3wherein the treatment solution additionally comprises a water repellent.5. A method of preparing a composite product as in claim 4 wherein thetreatment solution additionally comprises a inorganic pigment.
 6. Amethod of preparing a composite product as in claim 5 wherein saidtreatment solution is applied to said finishing layer prior to Step c.7. A method of preparing a composite product as in claim 1 wherein Stepa comprises providing at least a third veneer.
 8. A method of preparinga composite product as in claim 7 wherein said finishing layer and atleast one of said veneers which is not said finishing layer areimpregnated with biocides prior to Step c.
 9. A method of preparing acomposite product as in claim 8 wherein said finishing layer and atleast one of said veneers which is not said finishing layer have atleast one biocide in common.
 10. A method as in claim 1 whichadditionally comprises the steps of: a) providing one or more additionalveneers; and b) further assembling the first composite product and theone or more additional veneers into a second composite product.
 11. Amethod of preparing a composite product as in claim 9 wherein saidfinishing layer is impregnated with said biocide to a retention greaterthan that of said veneers which are not said finishing layer.
 12. Amethod of preparing a composite product as in claim 4 wherein said waterrepellant is one or more hydrophobic oils and/or paraffin waxes.
 13. Amethod of preparing a composite product as in claim 8 wherein saidfinishing layer and one of said veneers which is not said finishinglayer are impregnated with biocides, at least one of which is not inboth layers.
 14. A method of preparing a composite product as in claim 8wherein said finishing layer and one of said veneers which is not saidfinishing layer are impregnated with biocides, at least one of which isnot in both layers.
 15. A method of preparing a composite product as inclaim 5 wherein said treatment solution additionally comprises astrength-enhancing monomer.
 16. A method of preparing a compositeproduct as in claim 15 wherein said strength enhancing monomer ispoly-dicyclopentadiene.
 17. A method as in claim 7 wherein at least oneof said veneers in said first composite product is untreated.
 18. Acomposite product comprising of two or more veneers, wherein at leasttwo of said veneers have been differentially treated prior to assemblyinto the composite product.
 19. A composite product as in claim 1wherein the composite product comprises two veneers, and wherein theveneers are differentially treated.
 20. A composite product as in claim1 wherein the composite product comprises three or more veneers.
 21. Acomposite product as in claim 1 wherein differential treatment comprisestreating the veneers with a treatment compound such that each veneer istreated to one of at least two different retentions of said treatmentcompound and at least one veneer is treated to a retention differentthan the retention to which the others are treated.
 22. A compositeproduct as in claim 1 wherein differential treatment comprises treatingthe veneers with one or a combination of treatment compounds such thateach veneer is treated with at least one compound, and at least oneveneer is treated with a different combination of treatment compoundsthan at least one other veneer.